Graham posted his endorsement on Twitter. &ldquo;Proud to support @SenRonJohnson for Vice Chair of the Senate Republican Conference. Ron will be a great addition to our leadership team,&rdquo; Graham tweeted.

Like Johnson, Ayotte was elected last year with substantial tea party support. She also has been mentioned as a potential leadership candidate, but her decision to endorse Johnson for Conference vice chairman would appear to eliminate any immediate move into leadership on her part.

&ldquo;As a proven job creator, Ron will provide effective leadership as Republicans work to get America&rsquo;s economy moving. He embodies the spirit of the &lsquo;citizen legislator,&rsquo; and his background will bring a fresh skill set to our leadership team,&rdquo; Ayotte said in a statement.

Coburn and DeMint, who both won a second term in 2010, are among the more conservative members of the Republican Conference.

Blunt, a Congressional veteran with several years of service in House leadership under his belt, could be positioned to earn the support of establishment Republicans and moderates in any head-to-head campaign for Conference vice chairman against Johnson. Blunt, a former House Majority Whip, is currently a member of Minority Whip Jon Kyl&rsquo;s (Ariz.) whip team.